battery going flat. help needed

[aspir3]

As some of you know I have been having problems with my battery going flat for 2-3 months now.

It has all happened since I fitted the folding mirrors. Not sure if the mirrors are drawing to much power or if it is just the battery or the cold weather.

For those of you who do not know I do not drive my car more then once a month lately. In fact the last drive was SA's last cruise on the 17th of July.

My car is kept in a steel Garage with a concrete floor.

Last week I removed the battery from the car and charged it for about 12 hours. My charger has a gauge on it that shows how much charge the battery has. After charging it 4 out of the 5 lights were on. I left the battery in the garage(different to where the car is kept) on a wooden top. After 5 days I checked the battery and it still had 4 out of 5 lights on. So I take it the battery is OK.

I fitted the battery to the car and it started the engine fine.

I then did some tests on how many amps are being drawn from the battery.

It uses 0.04 amp while the car is in standby.

If I remove the 30 amp fuse under the hood which is for the keyless ignition, MMCS and the folding mirrors then it goes to 0.00 amps.

Now I do not know what is drawing 0.04 amp. I could not be bothered to disconnect the power to the folding mirrors as I dont think 0.04 amp is very much.

Does any know how many amp there car uses in standby?

I would be interested to know what others cars use. Especially those with MMCS.

Does any know what power the folding mirrors use while the car is in standby?

Is 0.04 amp more then normal?

Could it be just the cold weather?

[Blakey]

well its using 40mA and your battery should be like a 80 90Ah battery so it should last like 225,000Hrs with that current draw. and those lights your talking about on your charger what do they represent?

[aspir3]

They represent how much charge is in the battery.

With the battery charger turned off you put the leads on and the lights come on according to charge.

The battery would only light up 1 light which indicates flat.

4 lights indicate good/full.

Is 40mA more then usual?

[Blakey]

They represent how much charge is in the battery.

With the battery charger turned off you put the leads on and the lights come on according to charge.

The battery would only light up 1 light which indicates flat.

4 lights indicate good/full.

Is 40mA more then usual?

well i would say 40mA is normal. as you have you immobilizer keyless entry and that on there so it would require something wile the car was off.

[AJjnr86]

0,04A is about right, shouldn't b much more than that else u should b worried

[aspir3]

I think you need to start your car at least once a week for atleast 5min, this should solve your flat battery problem.

The computer in the car will be drawing a small current to run the clock and internal calender for service intervals. I cant see anything else pulling a current, do you have a car alarm installed as well?

If you say it has started when you put the folding mirrors on, take them off and see what happens.

How did you measure the current? If i were to do this, I'd take off the positive terminal from the battery and place the meter set to DC amps (or milli amps if it has the function) one lead on the battery terminal and other on the cable. This should show any thing being drawn from the battery

That is what I did but between the negative terminal and cable.

I do not have an alarm.

The 0.04 amps dropped to none when I removed the 30amp fuse that if for the MMCS, keyless start and folding mirrors.

[AJjnr86]

I think you need to start your car at least once a week for atleast 5min, this should solve your flat battery problem.

U will run ur battery flat if u only run it for 5minutes, the starter motor draws something ridiculous like 30 - 40 Amps, so takes bout 30 minutes of running to get that charge back in, best is to just go for a cruise every week

[scraverX]

It's possible your battery could have deteriorated due to repeated full discharge - depends a bit on the age of the battery and cold weather certainly wouldn't help.

Perhaps, take the car to an auto electrician and have them check the battery.

[AJjnr86]

Or automotive battery centre, my battery in my previous car only lasted 2.5 - 3 yrs before I had to replace it, and that car was band new when I got it

[aspir3]

Last night I checked solar controller which showed the battery fully charged.

This morning the controller was showing it was charging the battery with the light off indicating battery full. Obviously over night the accessories was enough to use some power from the battery.

Interesting will be if the solar panels recharge the battery before dark?

I suspect as others have said that the battery is on the way out. It has been allowed to go flat several times and needed to be recharged which shortens the life of the battery.

Just for the record the car was built in 09-08. So the battery is probably only 2 years old. Mitsubishi only cover the battery under warranty for 12 months.

I am hoping the solar panel helps the battery life. I fear buying a new battery will only end up doing the same as the cold weather and lack of use will flatten it. I do start my car every week for 5 minutes as well to bring the fluids up to temperature. Some times I even bring it out of the garage to give it a polish if the weather is good.

Lately I do go out there and show family and friend the folding mirrors as well.

I will keep you updated on the battery and the solar panels.

It should help all of us understand the life of the batteries in our cars.

[AJjnr86]

Haha, Ryan that's kool , most ppl don't no the starter uses that much, that's y a little old ladies car that she only uses every week to drive two minutes down the road to bingo will have more problems than a hoons car

[smithsy]

Whilst there are many different theories around rechargeable batteries, it's generally accepted that completely draining a battery isn't healthy for it. Extreme cold temps vs hot temps also play a significant part, believe it or not in a UPS more often than not the batteries on the top shelf are in worse condition than the batteries on the lower shelf, simply due to the slight difference in heat!!

If you do get the battery tested and find out it's packed it in, then definitely opt for a marine/deep-cycle battery as they are better designed for coping with and recovering properly from long discharge cycles...

As was said though the starter motor draws a very significant amount of power from the battery so really you probably want to be running the car for at least 10-15mins a week. Something else to keep in mind is too stick with a decent synthetic oil which will keep the upper internals of the motor better coated in oil ready for the next start-up (a cheap shitty oil will tend to drip back down moreso and provide inadequate protection on start-up, especially after being standing for a week). A thinner oil will also ensure that the oil flows to the top of the motor as quick as possible on start-up to coat the internals fully once the motor has started up.

Haha, Ryan that's kool , most ppl don't no the starter uses that much, that's y a little old ladies car that she only uses every week to drive two minutes down the road to bingo will have more problems than a hoons car

It's got nothing to do with the starter motor (this will only mean the battery packs it in more frequently), rather that the car has been operated most of it's time whilst it's internals aren't at operating temperatures and a cold motor is when you have the most damage done. That and the fact if anything they probably don't rev the motor up enough before changing gears and end up labouring the engine... But to say it's worse than some hoon who flogs the shit from their car that's probably a little bit out there...

[The X]

It uses 0.04 amp while the car is in standby.

If I remove the 30 amp fuse under the hood which is for the keyless ignition, MMCS and the folding mirrors then it goes to 0.00 amps.

Now I do not know what is drawing 0.04 amp. I could not be bothered to disconnect the power to the folding mirrors as I dont think 0.04 amp is very much.

Could well be the MMCS and stock head units to keep settings and station presets as they get lost when you disconnect the battery, they not stored in non-volatile memory.
Also keyless entry system would constantly have the keyless RF radio powered up all the time in anticipation of your proximity and the touch sensors under the handles.

Check it again maybe after 30 minutes or so without opening the doors and see if the 0.04 amp is still there. The ETACS has a feature to cut off power to cabin lights and the like after 30 minutes to avoid draining the battery.